To detect the genome of viruses (in environmental and clinical samples), we use electrophoresis running buffer after PCR reaction. Also, electrophoresis buffers were used widely to separate any DNA molecule. In this p...To detect the genome of viruses (in environmental and clinical samples), we use electrophoresis running buffer after PCR reaction. Also, electrophoresis buffers were used widely to separate any DNA molecule. In this paper, we used four types of previously known electrophoresis buffers to compare which is easy for preparation, simple in structure, low cost and good performance in agarose gel electrophoresis. For this, we used two agarose concentration (1%, 2%) and two types of DNA ladder (100 bp, 1 kb) represent both smaller and larger sizes of molecule for each type of buffers, from the result we found in first level both supper buffer and TAE buffer with good performance and in second level we found bicarbonate buffer also with good performance also. Finally, we found the tang buffer cannot pose any electrophoretic activity on DNA agarose gel electrophoresis.展开更多
A new capillary electrophoresis apparatus was designed. Piezoelectric ceramics transformer technology was first applied in capillary electrophoresis, a high voltage and stable source was made. Amperometric detector wa...A new capillary electrophoresis apparatus was designed. Piezoelectric ceramics transformer technology was first applied in capillary electrophoresis, a high voltage and stable source was made. Amperometric detector was used in which the working electrode was closely opposite to the end of capillary. The apparatus was characterized in good reproducibility, safety and very low cost.展开更多
To establish a suitable and effective protocol of protein extraction for two-dimensional gel electrophoresis (2-DE) analysis in kenaf leaf tissues, three extraction methods (trichloroacetic acid/acetone, urea/thiou...To establish a suitable and effective protocol of protein extraction for two-dimensional gel electrophoresis (2-DE) analysis in kenaf leaf tissues, three extraction methods (trichloroacetic acid/acetone, urea/thiourea, and phenol extraction methods) were applied to the extraction of kenaf leaf protein. The results were compared in regard to protein extraction efficiency, sodiumdodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and 2-DE gels. Furthermore, the 2-DE system was optimized for four aspects: the pH range of IPG (immobilized pH gradient) stripes, sampling methods, sample volumes, and concentration of polyacrylamide gels. The data presented showed that the phenol extraction method is the best method to perform 2-DE analysis of kenaf leaf protein. The protein extracted from phenol extraction method reached the purity of (26.40±0.859)%, showed (25.67±1.53) protein bands in one dimension SDS-PAGE gels, and (1 374±54.44) protein spots on 2-DE gels. The research also indicates that kenaf leaf protein spots were distributed mainly within the pH range of 4-8. More clear background with a better distribution effect and many protein spots could be obtained on 2-DE gels under the conditions of active rehydration loading, 24 cm IPG strips (linear pH gradient of 4-7), 1.4 mg samples, and 12% SDS-PAGE gels.展开更多
Objective Lower respiratory tract infections continue to pose a significant threat to human health. It is important to accurately and rapidly detect respiratory bacteria. To compensate for the limits of current respir...Objective Lower respiratory tract infections continue to pose a significant threat to human health. It is important to accurately and rapidly detect respiratory bacteria. To compensate for the limits of current respiratory bacteria detection methods, we developed a combination of multiplex polymerase chain reaction (PCR) and capillary electrophoresis (MPCE) assay to detect thirteen bacterial pathogens responsible for lower respiratory tract infections, including Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catorrholis, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus, Mycoplasma pneumoniae, Legionella spp., Bordetella pertussis, Mycobacterium tuberculosis complex, Corynebactefium diphthefiae, and Streptococcus pyogenes. Methods Three multiplex PCR reactions were built, and the products were analyzed by capillary electrophoresis using the high-throughput DNA analyzer. The specificity of the MPCE assay was examined and the detection limit was evaluated using DNA samples from each bacterial strain and the simulative samples of each strain. This assay was further evaluated using 152 clinical specimens and compared with real-time PCR reactions. For this assay, three nested-multiplex-PCRs were used to detect these clinical specimens. Results The detection limits of the MPCE assay for the 13 pathogens were very low and ranged from 10-7 to 10-2 ng/μL. Furthermore, analysis of the 252 clinical specimens yielded a specificity ranging from 96.5%-100.0%, and a sensitivity of 100.0% for the 13 pathogens. Conclusion This study revealed that the MPCE with high specificity and sensitivity. This assay survey of respiratory pathogens. assay is a rapid, reliable, and high-throughput method has great potential in the molecular epidemiological.展开更多
Globozoospermia is a severe form of teratozoospermia characterized by round-headed spermatozoa with an absent acrosome, an aberrant nuclear membrane and midpiece defects. Globozoospermia is diagnosed by the presence o...Globozoospermia is a severe form of teratozoospermia characterized by round-headed spermatozoa with an absent acrosome, an aberrant nuclear membrane and midpiece defects. Globozoospermia is diagnosed by the presence of 100% round-headed spermatozoa on semen analysis, and patients with this condition are absolutely infertile. The objective of this study was to investigate the differences in protein expression between human round- headed and normal spermatozoa. Two-dimensional (2-D) fluorescence difference gel electrophoresis (DIGE) coupled with mass spectrometry (MS) was used in this study. Over 61 protein spots were analysed in each paired normal/round-headed comparison, using DIGE technology along with an internal standard. In total, 35 protein spots identified by tandem mass spectrometry (MS/MS) exhibited significant changes (paired t-test, P 〈 0.05) in the expression level between normal and round-headed spermatozoa. A total of nine proteins were found to be upregulated and 26 proteins were found to be downregulated in round-headed spermatozoa compared with normal spermatozoa. The differentially expressed proteins that we identified may have important roles in a variety of cellular processes and structures, including spermatogenesis, cell skeleton, metabolism and spermatozoa motility.展开更多
A novel method for the determination of two quinolone drugs norfloxacin (NOR) and levofloxacin (LVX) was described by capillary electrophoresis with electrochemiluminescence detection. The good relationship (r ≥...A novel method for the determination of two quinolone drugs norfloxacin (NOR) and levofloxacin (LVX) was described by capillary electrophoresis with electrochemiluminescence detection. The good relationship (r ≥ 0.9991) between peak area and concentration of analytes was established over two orders of magnitude. The limits of detection (LOD, S/N = 3) in standard solution are 4.8 × 10^-7 mol/L for NOR and 6.4 × 10^-7 mol/L for LVX, respectively. The limits of quantitation (LOQ, S/N = 10) in real human urine samples are 1.2 × 10^-6 mol/L for NOR and 1.4 × 10^-6 mol/L for LVX, respectively. The present method was successfully applied to the determination of NOR and LVX in human urine and the studv of oharmacokinetics of NOR.展开更多
The mechanism of dispersion induced by turn in the capillary electrophoresis channel flows was analyzed firstly. Then the mathematical model of electroosmotic flow is built, and the dispersion of the flow, with differ...The mechanism of dispersion induced by turn in the capillary electrophoresis channel flows was analyzed firstly. Then the mathematical model of electroosmotic flow is built, and the dispersion of the flow, with different distribution of charge at inner and outer wall in the turns, was simulated numerically using the finite differential method. A new approach of altering the distribution of charge at inner and outer wall in the turns was presented, based on the computational results, to minimize the dispersion induced by turn. Meanwhile, an optimization algorithm to analyze the numerical results and determine the optimal distribution of charge in the turns was also developed. It is found that the dispersion induced by turn in the capillary electrophoresis channel flows could be significantly suppressed by this approach.展开更多
A sensitive, simple and low-cost method based on capillary electrophoresis(CE) with electrochemical(EC) detection at a carbon fiber microdisk electrode(CFE) was developed for the determination of nicotine. Effec...A sensitive, simple and low-cost method based on capillary electrophoresis(CE) with electrochemical(EC) detection at a carbon fiber microdisk electrode(CFE) was developed for the determination of nicotine. Effects of de- tection potential, concentration and pH value of the phosphate buffer, and injection time as well as separation voltage were investigated. Under the optimized conditions: a detection potential of 1.20 V, 40 rnmol/L phosphate buffer(pH 2.0), a sample injection time of 10 s at 10 kV and a separation voltage of 16 kV, the linear range obtained was from 5.0×10^-7 mol/L to 1.0×10^-4 mol/L with a correlation coefficient of 0.9989 and the limit of detection(LOD, S/N=3) obtained was 5.0×10^-8 mol/L. The method was also used to determine the nicotine in cigarettes. Nicotine amount ranged from 0.211 mg/g to 0.583 mg/g in the pipe tobacco of seven brands of cigarette and the amount in one ciga- rette varied from 0.136 mg/cigarette to 0.428 mg/cigarette.展开更多
A high-performance capillary electrophoresis with amperometry detection method (CE-AD) has been developed for the analysis of flavonoids and anthraquinones (emodin, kaempferol, apigenin, luteolin and rhein) in chr...A high-performance capillary electrophoresis with amperometry detection method (CE-AD) has been developed for the analysis of flavonoids and anthraquinones (emodin, kaempferol, apigenin, luteolin and rhein) in chrysanthemum. Under optimum conditions, these five analytes were base-line separated within 17 min using a borate-phosphate running buffer (1.5 ×10^-2 mol/L borate-3× 10^-2 mol/L phosphate running buffer, pH 9.0) at a working potential of +0.90 V (vs. SCE) and a separation voltage of 19 kV. The linear relationship between concentration and current response was obtained with detection limits (S/N = 3) ranging from 1.0 × 10^-7 to 2.1 × 10^-7 g/mL for all analytes. This proposed method was successfully used in the analysis of four kinds of chrysanthemum with relatively simple extraction procedures, the assay results were satisfactory.展开更多
Two active principles in traditional Chinese medicine Magnolia officinalis, magnolol and honokiol, were successfully separated by means of nonaqueous capillary electrophoresis. The effect of the composition of a nonaq...Two active principles in traditional Chinese medicine Magnolia officinalis, magnolol and honokiol, were successfully separated by means of nonaqueous capillary electrophoresis. The effect of the composition of a nonaqueous buffer on column efficiency and resolution, and the effect of acid additives on peak shapes were researched. The separation was conducted with a running buffer in a mixture of methanol/aeetonitrile/formamide ( volume ratio : 1 : 2 : 2 ), in which the concentrations of Tris, acetic acid, and water were 60 retool/L, 0. 04 mmol/L and 5% ( volume fration), respectively, and the pH^* (apperent pH) of the running buffer was 8.96. Magnolol and honokiol were separated on baseline within 20 min. The relative standard deviation of the analytes' concentrations in the sample is 1.32% for magnolol and 1.60% for honokiol, and the recoveries of the spiked sample are 98.4% for magnolol and 98. 0% for honokiol, respectively.展开更多
The characterization of microbial communities of different depth sediment samples was examined by a culture-independent method and compared with physicochemical parameters, those are organic matter (OM), total nitro...The characterization of microbial communities of different depth sediment samples was examined by a culture-independent method and compared with physicochemical parameters, those are organic matter (OM), total nitrogen (TN), total phosphorus (TP), pH and redox potential (Eh). Total genomic DNA was extracted from samples derived from different depths. After they were amplified with the GC-341 f/907r primer sets of partial bacterial 16S rRNA genes, the products were separated by denaturing gradient gel electrophoresis (DGGE). The profile of DGGE fingerprints of different depth sediment samples revealed that the community structure remained relatively stable along the entire 45 cm sediment core, however, principal-component analysis of DGGE patterns revealed that at greater sediment depths, successional shifts in community structure were evident. The principle coordinates analysis suggested that the bacterial communities along the sediment core could be separated into two groups, which were located 0-20 cm and 21-45 cm, respectively. The sequencing dominant bands demonstrated that the major phylogenetic groups identified by DGGE belonged to Bacillus, Bacterium, Brevibacillus, Exiguobacterium, γ-Proteobacterium, Acinetobacter sp. and some uncultured or unidentified bacteria. The results indicated the existence of highly diverse bacterial community in the lake sediment core.展开更多
Guillain-Barre syndrome (GBS) is considered to be an autoimmune disorder of peripheralnervous system. In this paper. capillary SDS gel electrophoresis was performed on neutral coatedfused-silica capillary to determine...Guillain-Barre syndrome (GBS) is considered to be an autoimmune disorder of peripheralnervous system. In this paper. capillary SDS gel electrophoresis was performed on neutral coatedfused-silica capillary to determine the molecular weight of purified IgG samples from GBS patient.展开更多
Urinary 8-hydroxy-2 -deoxyguanosine(8-OHdG) is an excellent marker of oxidative DNA damage.In this study,employing guanosine as dummy template a novel molecularly imprinted(MIP) monolithic capillary column had been sy...Urinary 8-hydroxy-2 -deoxyguanosine(8-OHdG) is an excellent marker of oxidative DNA damage.In this study,employing guanosine as dummy template a novel molecularly imprinted(MIP) monolithic capillary column had been synthesized,and that was used as medium of in-tube solid phase microextraction(SPME).Coupled with capillary electrophoresis-electrochemical detection(CE-ECD),the system of extraction and detection of 8-OHdG in urinary sample had been developed.Because of its greater phase ratio combined with conv...展开更多
Based on the fact that some metal ions can catalyze the chemiluminescence(CL)reaction of luminol with K_3Fe(CN)_6,a novel capillary electrophoresis CL method was developed for the determination of Co(Ⅱ)and Cu(Ⅱ).The...Based on the fact that some metal ions can catalyze the chemiluminescence(CL)reaction of luminol with K_3Fe(CN)_6,a novel capillary electrophoresis CL method was developed for the determination of Co(Ⅱ)and Cu(Ⅱ).The separation was carried out with a 10 mmol/L sodium acetate solution containing 0.8 mmol/L luminol and 2.0 mmol/Lα-HIBA(adjusted to pH 4.8 by HAc solution).The post-capillary reagent was 2.0 mmol/L K_3Fe(CN)_6 which was adjusted to pH 13.0 by NaOH solution.Under the optimum conditions,the detection limits(S/N=3)for Co(Ⅱ)and Cu(Ⅱ)were 7.5×10^(-11)mol/L and 7.5×10^(-9)mol/L,with the linear range of 7.5×10^(-9)mol/L to 1.0×10^(-6)mol/L and 7.5×10^(-8)mol/L to 5.0×10^(-5)mol/L, respectively.展开更多
To compare the protein difference between B. henselae Houston and B. henselae Marseille by two-dimensional gel electrophoresis. Method Protein samples were prepared by vorterx, ultrasonic treatment, and centrifugation...To compare the protein difference between B. henselae Houston and B. henselae Marseille by two-dimensional gel electrophoresis. Method Protein samples were prepared by vorterx, ultrasonic treatment, and centrifugation. Protein concentrations were determined by Bradford method. Protein difference was compared by the first IEF and the second SDS-polyacrylamide gel electrophoresis. Results Protein concentrations in samples of Bartonella henselae Houston and Bartonella henselae Marseille were 2.117 μg/μL and 2.200 μg/μL respectively. Sample protein of 40 μg for IPG strips loading was perfect. The results of 2-DE in pH 4 to 7 IPG strips showed that the total protein spots of Bartonella henselae Houston and Bartonella henselae Marseille were 375 and 379 respectively, 95% of the spots were the same between the two strains of Bartonella henselae. Conclusion The procedure of 2-DE may prove successful for the proteomic analysis of Bartonella henselae. Bartonella henselae Houston and Bartonella henselae Marseille are different genotypes.展开更多
The water-soluble carboxymethyl-cyclodextrin polymer (CM-CD polymer) was synthesized and used as capillary electrophoresis chiral selector. Verrapamil and thiopentorusodium were well separated using CM-CD polymer as c...The water-soluble carboxymethyl-cyclodextrin polymer (CM-CD polymer) was synthesized and used as capillary electrophoresis chiral selector. Verrapamil and thiopentorusodium were well separated using CM-CD polymer as chiral selector.展开更多
A high-performance capillary electrophoresis with amperometric detection(CE-AD) method has been developed for the analysis of seven bioactive ingredients,namely ferulic acid(FA),vanillin,vanillic acid,p-hydroxybenzoic...A high-performance capillary electrophoresis with amperometric detection(CE-AD) method has been developed for the analysis of seven bioactive ingredients,namely ferulic acid(FA),vanillin,vanillic acid,p-hydroxybenzoic acid,caffeic acid,gallic acid and protocatechuic acid,in Rhizoma Chuanxiong.The effects of several factors such as the acidity and concentration of running buffer,the separation voltage,the applied potential to working electrode and the injection time were investigated.Under the optimum condit...展开更多
A capillary electrophoresis (CE) method has been firstly used for the separation of the therapeutically important xanthones from Securidaca inappendiculata. The separation of the nine xanthones was systematically opt...A capillary electrophoresis (CE) method has been firstly used for the separation of the therapeutically important xanthones from Securidaca inappendiculata. The separation of the nine xanthones was systematically optimized with respect to pH, concentration of running buffers, addition of sulfated b-CD, applied voltage and column temperature. Baseline separation was achieved for the nine xanthones in less than 15 minutes using a background electrolyte consisting of 200 mmol/L borate (pH 9.5) and 10 mmol/L sulfated b-CD.展开更多
Capillary electrophoresis with many advantages plays an important role in pharmaceutical analysis and drug screening. This review gives an overview on the recent advances in the developments and applications of capill...Capillary electrophoresis with many advantages plays an important role in pharmaceutical analysis and drug screening. This review gives an overview on the recent advances in the developments and applications of capillary electrophoresis in the field of enzyme inhibitor screening. The period covers 2013 to 2017. Both the pre-capillary enzyme assays and in-capillary enzyme assays which include electrophoretically mediated microanalysis(EMMA) and immobilized enzyme microreactor(IMER) are summarized in this article.展开更多
文摘To detect the genome of viruses (in environmental and clinical samples), we use electrophoresis running buffer after PCR reaction. Also, electrophoresis buffers were used widely to separate any DNA molecule. In this paper, we used four types of previously known electrophoresis buffers to compare which is easy for preparation, simple in structure, low cost and good performance in agarose gel electrophoresis. For this, we used two agarose concentration (1%, 2%) and two types of DNA ladder (100 bp, 1 kb) represent both smaller and larger sizes of molecule for each type of buffers, from the result we found in first level both supper buffer and TAE buffer with good performance and in second level we found bicarbonate buffer also with good performance also. Finally, we found the tang buffer cannot pose any electrophoretic activity on DNA agarose gel electrophoresis.
文摘A new capillary electrophoresis apparatus was designed. Piezoelectric ceramics transformer technology was first applied in capillary electrophoresis, a high voltage and stable source was made. Amperometric detector was used in which the working electrode was closely opposite to the end of capillary. The apparatus was characterized in good reproducibility, safety and very low cost.
基金supported by the Project of Fiber Crops Industrial System Construction in China (nycytx-19-E05)the Natural Public Welfare Sector Projects of China(nyhyzx07-018)the Transformation Program of Agricultural Science and Technology Achievements in China (20dnfq2c400170)
文摘To establish a suitable and effective protocol of protein extraction for two-dimensional gel electrophoresis (2-DE) analysis in kenaf leaf tissues, three extraction methods (trichloroacetic acid/acetone, urea/thiourea, and phenol extraction methods) were applied to the extraction of kenaf leaf protein. The results were compared in regard to protein extraction efficiency, sodiumdodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and 2-DE gels. Furthermore, the 2-DE system was optimized for four aspects: the pH range of IPG (immobilized pH gradient) stripes, sampling methods, sample volumes, and concentration of polyacrylamide gels. The data presented showed that the phenol extraction method is the best method to perform 2-DE analysis of kenaf leaf protein. The protein extracted from phenol extraction method reached the purity of (26.40±0.859)%, showed (25.67±1.53) protein bands in one dimension SDS-PAGE gels, and (1 374±54.44) protein spots on 2-DE gels. The research also indicates that kenaf leaf protein spots were distributed mainly within the pH range of 4-8. More clear background with a better distribution effect and many protein spots could be obtained on 2-DE gels under the conditions of active rehydration loading, 24 cm IPG strips (linear pH gradient of 4-7), 1.4 mg samples, and 12% SDS-PAGE gels.
基金supported by grants from the Priority Project on Infectious Disease Control and Prevention(2012ZX10004215,2013ZX10004610)from Ministry of Health,China,and the Science Foundation for the State Key Laboratory for Infectious Disease Prevention and Control from China(Grant No.2015SKLID508)the National Natural Science Foundation of China(Grant No.81671985)and(Grant No.81170009)
文摘Objective Lower respiratory tract infections continue to pose a significant threat to human health. It is important to accurately and rapidly detect respiratory bacteria. To compensate for the limits of current respiratory bacteria detection methods, we developed a combination of multiplex polymerase chain reaction (PCR) and capillary electrophoresis (MPCE) assay to detect thirteen bacterial pathogens responsible for lower respiratory tract infections, including Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catorrholis, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus, Mycoplasma pneumoniae, Legionella spp., Bordetella pertussis, Mycobacterium tuberculosis complex, Corynebactefium diphthefiae, and Streptococcus pyogenes. Methods Three multiplex PCR reactions were built, and the products were analyzed by capillary electrophoresis using the high-throughput DNA analyzer. The specificity of the MPCE assay was examined and the detection limit was evaluated using DNA samples from each bacterial strain and the simulative samples of each strain. This assay was further evaluated using 152 clinical specimens and compared with real-time PCR reactions. For this assay, three nested-multiplex-PCRs were used to detect these clinical specimens. Results The detection limits of the MPCE assay for the 13 pathogens were very low and ranged from 10-7 to 10-2 ng/μL. Furthermore, analysis of the 252 clinical specimens yielded a specificity ranging from 96.5%-100.0%, and a sensitivity of 100.0% for the 13 pathogens. Conclusion This study revealed that the MPCE with high specificity and sensitivity. This assay survey of respiratory pathogens. assay is a rapid, reliable, and high-throughput method has great potential in the molecular epidemiological.
基金Acknowledgment We thank Beijing Proteome Research Center, (Beijing, China) for its enthusiastic technological support and for the theory of 2-D DIGE. We also thank(Changsha, China) College of Life Sciences at Hunan Normal University for supporting the MS technology. Finally, we are very grateful to our collaborators for their help, as well as their valuable discussions and suggestions during the course of this work. This work was supported by two grants from the National Natural Science Foundation of China (NO. 30170480 and NO. 30470884).
文摘Globozoospermia is a severe form of teratozoospermia characterized by round-headed spermatozoa with an absent acrosome, an aberrant nuclear membrane and midpiece defects. Globozoospermia is diagnosed by the presence of 100% round-headed spermatozoa on semen analysis, and patients with this condition are absolutely infertile. The objective of this study was to investigate the differences in protein expression between human round- headed and normal spermatozoa. Two-dimensional (2-D) fluorescence difference gel electrophoresis (DIGE) coupled with mass spectrometry (MS) was used in this study. Over 61 protein spots were analysed in each paired normal/round-headed comparison, using DIGE technology along with an internal standard. In total, 35 protein spots identified by tandem mass spectrometry (MS/MS) exhibited significant changes (paired t-test, P 〈 0.05) in the expression level between normal and round-headed spermatozoa. A total of nine proteins were found to be upregulated and 26 proteins were found to be downregulated in round-headed spermatozoa compared with normal spermatozoa. The differentially expressed proteins that we identified may have important roles in a variety of cellular processes and structures, including spermatogenesis, cell skeleton, metabolism and spermatozoa motility.
基金the National Natural Science Foundation of China(No.20575056)Henan Innovation Project for University Research Talents(No.2005126).
文摘A novel method for the determination of two quinolone drugs norfloxacin (NOR) and levofloxacin (LVX) was described by capillary electrophoresis with electrochemiluminescence detection. The good relationship (r ≥ 0.9991) between peak area and concentration of analytes was established over two orders of magnitude. The limits of detection (LOD, S/N = 3) in standard solution are 4.8 × 10^-7 mol/L for NOR and 6.4 × 10^-7 mol/L for LVX, respectively. The limits of quantitation (LOQ, S/N = 10) in real human urine samples are 1.2 × 10^-6 mol/L for NOR and 1.4 × 10^-6 mol/L for LVX, respectively. The present method was successfully applied to the determination of NOR and LVX in human urine and the studv of oharmacokinetics of NOR.
基金Project supported by the National Natural Science Foundation of China (No. 20299030)
文摘The mechanism of dispersion induced by turn in the capillary electrophoresis channel flows was analyzed firstly. Then the mathematical model of electroosmotic flow is built, and the dispersion of the flow, with different distribution of charge at inner and outer wall in the turns, was simulated numerically using the finite differential method. A new approach of altering the distribution of charge at inner and outer wall in the turns was presented, based on the computational results, to minimize the dispersion induced by turn. Meanwhile, an optimization algorithm to analyze the numerical results and determine the optimal distribution of charge in the turns was also developed. It is found that the dispersion induced by turn in the capillary electrophoresis channel flows could be significantly suppressed by this approach.
基金Supported by the National Natural Science Foundation of China(No.20875085)
文摘A sensitive, simple and low-cost method based on capillary electrophoresis(CE) with electrochemical(EC) detection at a carbon fiber microdisk electrode(CFE) was developed for the determination of nicotine. Effects of de- tection potential, concentration and pH value of the phosphate buffer, and injection time as well as separation voltage were investigated. Under the optimized conditions: a detection potential of 1.20 V, 40 rnmol/L phosphate buffer(pH 2.0), a sample injection time of 10 s at 10 kV and a separation voltage of 16 kV, the linear range obtained was from 5.0×10^-7 mol/L to 1.0×10^-4 mol/L with a correlation coefficient of 0.9989 and the limit of detection(LOD, S/N=3) obtained was 5.0×10^-8 mol/L. The method was also used to determine the nicotine in cigarettes. Nicotine amount ranged from 0.211 mg/g to 0.583 mg/g in the pipe tobacco of seven brands of cigarette and the amount in one ciga- rette varied from 0.136 mg/cigarette to 0.428 mg/cigarette.
基金financially supported by The Program for New Century Excellent Talents in University
文摘A high-performance capillary electrophoresis with amperometry detection method (CE-AD) has been developed for the analysis of flavonoids and anthraquinones (emodin, kaempferol, apigenin, luteolin and rhein) in chrysanthemum. Under optimum conditions, these five analytes were base-line separated within 17 min using a borate-phosphate running buffer (1.5 ×10^-2 mol/L borate-3× 10^-2 mol/L phosphate running buffer, pH 9.0) at a working potential of +0.90 V (vs. SCE) and a separation voltage of 19 kV. The linear relationship between concentration and current response was obtained with detection limits (S/N = 3) ranging from 1.0 × 10^-7 to 2.1 × 10^-7 g/mL for all analytes. This proposed method was successfully used in the analysis of four kinds of chrysanthemum with relatively simple extraction procedures, the assay results were satisfactory.
文摘Two active principles in traditional Chinese medicine Magnolia officinalis, magnolol and honokiol, were successfully separated by means of nonaqueous capillary electrophoresis. The effect of the composition of a nonaqueous buffer on column efficiency and resolution, and the effect of acid additives on peak shapes were researched. The separation was conducted with a running buffer in a mixture of methanol/aeetonitrile/formamide ( volume ratio : 1 : 2 : 2 ), in which the concentrations of Tris, acetic acid, and water were 60 retool/L, 0. 04 mmol/L and 5% ( volume fration), respectively, and the pH^* (apperent pH) of the running buffer was 8.96. Magnolol and honokiol were separated on baseline within 20 min. The relative standard deviation of the analytes' concentrations in the sample is 1.32% for magnolol and 1.60% for honokiol, and the recoveries of the spiked sample are 98.4% for magnolol and 98. 0% for honokiol, respectively.
基金This work was supported by the National Basic Research Program (973) of China (No. 2002CB412307) the Hi-Tech Research and Development Program (863) of China (No. 2002AA601011) the National Natural Science Foundation of China (No. 40371102).
文摘The characterization of microbial communities of different depth sediment samples was examined by a culture-independent method and compared with physicochemical parameters, those are organic matter (OM), total nitrogen (TN), total phosphorus (TP), pH and redox potential (Eh). Total genomic DNA was extracted from samples derived from different depths. After they were amplified with the GC-341 f/907r primer sets of partial bacterial 16S rRNA genes, the products were separated by denaturing gradient gel electrophoresis (DGGE). The profile of DGGE fingerprints of different depth sediment samples revealed that the community structure remained relatively stable along the entire 45 cm sediment core, however, principal-component analysis of DGGE patterns revealed that at greater sediment depths, successional shifts in community structure were evident. The principle coordinates analysis suggested that the bacterial communities along the sediment core could be separated into two groups, which were located 0-20 cm and 21-45 cm, respectively. The sequencing dominant bands demonstrated that the major phylogenetic groups identified by DGGE belonged to Bacillus, Bacterium, Brevibacillus, Exiguobacterium, γ-Proteobacterium, Acinetobacter sp. and some uncultured or unidentified bacteria. The results indicated the existence of highly diverse bacterial community in the lake sediment core.
文摘Guillain-Barre syndrome (GBS) is considered to be an autoimmune disorder of peripheralnervous system. In this paper. capillary SDS gel electrophoresis was performed on neutral coatedfused-silica capillary to determine the molecular weight of purified IgG samples from GBS patient.
基金the support of the National Natural Science Foundation of China(No.20575051).
文摘Urinary 8-hydroxy-2 -deoxyguanosine(8-OHdG) is an excellent marker of oxidative DNA damage.In this study,employing guanosine as dummy template a novel molecularly imprinted(MIP) monolithic capillary column had been synthesized,and that was used as medium of in-tube solid phase microextraction(SPME).Coupled with capillary electrophoresis-electrochemical detection(CE-ECD),the system of extraction and detection of 8-OHdG in urinary sample had been developed.Because of its greater phase ratio combined with conv...
文摘Based on the fact that some metal ions can catalyze the chemiluminescence(CL)reaction of luminol with K_3Fe(CN)_6,a novel capillary electrophoresis CL method was developed for the determination of Co(Ⅱ)and Cu(Ⅱ).The separation was carried out with a 10 mmol/L sodium acetate solution containing 0.8 mmol/L luminol and 2.0 mmol/Lα-HIBA(adjusted to pH 4.8 by HAc solution).The post-capillary reagent was 2.0 mmol/L K_3Fe(CN)_6 which was adjusted to pH 13.0 by NaOH solution.Under the optimum conditions,the detection limits(S/N=3)for Co(Ⅱ)and Cu(Ⅱ)were 7.5×10^(-11)mol/L and 7.5×10^(-9)mol/L,with the linear range of 7.5×10^(-9)mol/L to 1.0×10^(-6)mol/L and 7.5×10^(-8)mol/L to 5.0×10^(-5)mol/L, respectively.
文摘To compare the protein difference between B. henselae Houston and B. henselae Marseille by two-dimensional gel electrophoresis. Method Protein samples were prepared by vorterx, ultrasonic treatment, and centrifugation. Protein concentrations were determined by Bradford method. Protein difference was compared by the first IEF and the second SDS-polyacrylamide gel electrophoresis. Results Protein concentrations in samples of Bartonella henselae Houston and Bartonella henselae Marseille were 2.117 μg/μL and 2.200 μg/μL respectively. Sample protein of 40 μg for IPG strips loading was perfect. The results of 2-DE in pH 4 to 7 IPG strips showed that the total protein spots of Bartonella henselae Houston and Bartonella henselae Marseille were 375 and 379 respectively, 95% of the spots were the same between the two strains of Bartonella henselae. Conclusion The procedure of 2-DE may prove successful for the proteomic analysis of Bartonella henselae. Bartonella henselae Houston and Bartonella henselae Marseille are different genotypes.
文摘The water-soluble carboxymethyl-cyclodextrin polymer (CM-CD polymer) was synthesized and used as capillary electrophoresis chiral selector. Verrapamil and thiopentorusodium were well separated using CM-CD polymer as chiral selector.
基金the financial support provided by the National Science Foundation of China(No. 20875032)the Basic Research Fund of the Science and Technology Commission of Shanghai Municipality(No. 09ZR1409700)
文摘A high-performance capillary electrophoresis with amperometric detection(CE-AD) method has been developed for the analysis of seven bioactive ingredients,namely ferulic acid(FA),vanillin,vanillic acid,p-hydroxybenzoic acid,caffeic acid,gallic acid and protocatechuic acid,in Rhizoma Chuanxiong.The effects of several factors such as the acidity and concentration of running buffer,the separation voltage,the applied potential to working electrode and the injection time were investigated.Under the optimum condit...
基金The authors would like to acknowledge Agilent Technologies for providing the capillary electrophoresis system and Bioanalytical System for present of sulfated b-CD. The study is supported by NSFC Grant No. 29875001.
文摘A capillary electrophoresis (CE) method has been firstly used for the separation of the therapeutically important xanthones from Securidaca inappendiculata. The separation of the nine xanthones was systematically optimized with respect to pH, concentration of running buffers, addition of sulfated b-CD, applied voltage and column temperature. Baseline separation was achieved for the nine xanthones in less than 15 minutes using a background electrolyte consisting of 200 mmol/L borate (pH 9.5) and 10 mmol/L sulfated b-CD.
基金financial support from the National Natural Science Foundation of China (Grant nos. 81573384 and 21375101)
文摘Capillary electrophoresis with many advantages plays an important role in pharmaceutical analysis and drug screening. This review gives an overview on the recent advances in the developments and applications of capillary electrophoresis in the field of enzyme inhibitor screening. The period covers 2013 to 2017. Both the pre-capillary enzyme assays and in-capillary enzyme assays which include electrophoretically mediated microanalysis(EMMA) and immobilized enzyme microreactor(IMER) are summarized in this article.